It's really clear that folks don't
a) understand the market twilio is trying to serve
b) been in this market.
This guy probably is not checking is error codes. Twilio will always give you 30007 in these cases.
https://support.twilio.com/hc/en-us/articles/360008704834-Er...
Almost certainly this guy failed to follow their messaging guidelines. If you send (or forward) spam that includes links to third party websites or URL shorteners THEY TELL YOU that may trigger spam / blocking behavior.
And yes, this needs to be a zero tolerance game - with spammers the reasonable limits turn into 100 accounts being setup by folks in india for someone for 20 cents an account.